Evaluation of subterranean formations may involve using computers to generate models that simulate the formation. These models may provide an effective method of obtaining a better understanding of the formation. Some formation models may be generated by obtaining seismic data of the formation and then performing an inversion process using the obtained seismic data to identify one or more formation properties used to generate the model. In some instances, some data used in connection with these inversions may be calculated based on the Bantzle & Wang model.